Solvents are used to dissolve a material or extract one material from another. The most commonly used solvent is water, but many other compounds are used alone or in conjunction with water to dissolve water insoluble substances.

Solvents are typically divided into polar and nonpolar types. Polar solvents, such as water, consist of molecules that have an uneven electric charge, resulting in a positive charge on one end; nonpolar solvents have molecules with an evenly distributed charge. Typically, solvents are used to dissolve substances that have a similar polarity. For example, table salt is a polar compound that dissolves easily in water, where nonpolar substances such as oil don’t dissolve in water. Oil must be dissolved in a nonpolar solvent, such as hexane. Different solvents have different solubilities, or the maximum amount of solute that will dissolve in a specific volume of solvent at a particular temperature.

Solvents are used to dissolve a material or extract one material from another. The most commonly used solvent is water, but many other compounds are used alone or in conjunction with water to dissolve water insoluble substances.

Solvents are typically divided into polar and nonpolar types. Polar solvents, such as water, consist of molecules that have an uneven electric charge, resulting in a positive charge on one end; nonpolar solvents have molecules with an evenly distributed charge. Typically, solvents are used to dissolve substances that have a similar polarity. For example, table salt is a polar compound that dissolves easily in water, where nonpolar substances such as oil don’t dissolve in water. Oil must be dissolved in a nonpolar solvent, such as hexane. Different solvents have different solubilities, or the maximum amount of solute that will dissolve in a specific volume of solvent at a particular temperature.

Solvents are used in a wide variety of applications and include compounds for dry cleaning and spot cleaning, as components of detergents and perfumes, paint thinner, and glue solvents. Solvents are also used with particular reactants and reagents in chemical syntheses to produce specific chemical compounds. Common solvents include toluene, which is used as a paint thinner; acetone, which is used as a glue solvent or nail polish remover; and ethanol, which is a common solvent in making perfumes. Alcohol is a common solvent and includes a variety of substances such as ethanol and methanol. Ethanol and methanol are known as polar protic solvents; they are compounds that have a hydrogen atom attached to an electrically negative atom, most commonly oxygen.

Solvents are frequently used in industrial processes including pharmaceutical manufacturing, metal cleaning and degreasing, and paint remover manufacturing. Solvents used in industrial processes can be toxic and volatile and require careful handling. Methylene chloride is a popular solvent in industrial chemical manufacture, but is a potential carcinogen. Other solvents that require special storage and usage include benzene, diethyl ether, and sodium hydroxide.